Just from what I have read, you are set up for failure.
First is the 110 flux-core welder.
Second, I hope you are not even trying to run it on an extension cord.
What I would do is clean everything up for a clean weld, tack the pieces where you want them.
Talk to a local voc-tech school, every high school has one near-by.
Make a donation for school supply's, have the welding teacher, weld it the rest of the way together for you.
The welds will be nice and strong, plus you can learn some welding tricks for a small donation.